How it works: Vitamin K is a fat soluble vitamin that plays an important role in blood clotting. It is unlikely that the topical application of vitamin K alters the normal production of clotting factors by the liver. Currently, the thought is

that the benefits of vitamin K for the skin are derived from some unknown peripheral effects.

Effectiveness: Vitamin K has been shown in studies to help decrease the puffiness and discoloration that often results under the eyes as a result of aging, genetics, or sun damage. This effect may be further enhanced by using products that combine vitamin K and retinol. In addition, there have been several studies showing the effects of vitamin K in reducing bruising after laser therapy. The main benefit is a reduction in the intensity of bruising. Vitamin K cannot completely eliminate the risk of bruising after laser therapy. In all studies, topical vitamin K was very well tolerated with no irritation.

Where to find it: Products including those from Glytone Gly Derm and Petere Thomas Roth

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